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It’s the Final Countdown!!! Keystone Review Module 2 Cell Growth and Reproduction Genetics Theory of Evolution Ecology Standards…… Describe the events that occur during the cell cycle: interphase, mitosis (nuclear division) or cytokinesis. Mitosis Purpose of Mitosis Cell Growth Repair and replacement of damaged cell parts Asexual reproduction Cell Cycle Mitosis Meiosis Purpose of meiosis is chromosomal reduction. It only occurs in the organs that produce sex cells. Reduction division because it reduces the number of chromosomes in half TOOOOOO produce sex cells/gametes! Mitosis vs. Meiosis Mitosis and Meiosis Standard Compare the processes and outcomes of mitotic and meiotic divisions Mitosis and Meiosis Standard Compare the processes and outcomes of mitotic and meiotic divisions Mitosis and Meiosis Comparison Chart Mitosis and Meiosis Standard Check Which part of the flower produces cells by meiosis? a. Style b. Anther c. Stigma d. filament Mitosis and Meiosis Standard Check Which part of the flower produces cells by meiosis? a. Style b. Anther produces pollen which are male reproductive cells c. Stigma d. filament Mitosis and Meiosis CRQ…….Standard Check Patau syndrome can be a lethal genetic disorder in mammals, resulting from chromosomes failing to separate during meiosis. Identify the step during the process of meiosis when chromosomes would most likely fail to separate. Describe how chromosome separation in meiosis is different from chromosome separation in mitosis. Compare the effects of a disorder caused by chromosomes failing to separate during meiosis, to the effects of chromosomes failing to separate during mitosis. Standard Describe how the process of DNA replication results in the transmission and/or conservation of genetic information. DNA DNA is a polymer, long chain, of nucleotides. These molecules contain the genetic information of the cell. DNA is a nucleic acid DNA DNA Double helix Strands are complementary- which means that each DNA strand has the information to construct the other strand DNA is One strand runs in the 3’ to 5’ direction and the other runs in the 5’ to 3’ direction DNA follows semi-conservative replication anti-parallel DNA DNA Replication Process Helicase unwinds the DNA double helix and separates it into two strands Y-shaped replication fork will form as the double unwinds Single-stranded DNA binding proteins help keep the strands separate and prevent the strands from getting back together This process will continue until the entire molecule has been replicated DNA DNA Replication Process DNA Standard Check Which process helps to preserve the genetic information stored in DNA during DNA replication? a. The replacement of nitrogen base thymine with uracil b. Enzymes quickly linking nitrogen bases with hydrogen bonds c. The synthesis of unique sugar and phosphate molecules fro each nucleotide d. Nucleotides lining up along template strand according to base pairing rules DNA Standard Check Which process helps to preserve the genetic information stored in DNA during DNA replication? a. The replacement of nitrogen base thymine with uracil b. Enzymes quickly linking nitrogen bases with hydrogen bonds c. The synthesis of unique sugar and phosphate molecules fro each nucleotide d. Nucleotides lining up along template strand according to base pairing rules Standard Explain the functional relationships between DNA, genes, alleles, and chromosmes and their roles in inheritance. Genetics Genetics is the study of heredity. Heredity involves the transmission of genetic characteristics Genetics-Vocabulary Trait-physical characteristic Chromosome-long stringy aggregate of genes that carries heredity information and is formed from condensed chromatin Gene-segment of DNA that provides instructions for a particular trait Allele-alternative form of a gene Genetics-Vocabulary Trait-physical characteristic Chromosome-long stringy aggregate of genes that carries heredity information and is formed from condensed chromatin Gene-segment of DNA that provides instructions for a particular trait Allele-alternative form of a gene Homozygous-same Heterozygous-different Genetics-Vocabulary Genetics-Vocabulary Genotype-genetic makeup of an organism Phenotype- physical appearance of the organism Genetics-Practice Make sure you know how to draw and interpret a Punnett Square GeneticsStandard Practice In rabbits, black fur (B) is dominant over brown fur (b). If one parent rabbit is homozygous brown (bb), what is the probability of producing an offspring with brown fur? Use the Punnett square to determine your answer. Give the phenotype and genotype ratios. GeneticsStandard Practice Give the phenotype and genotype ratios. GeneticsIncomplete dominance Incomplete dominance- traits in which the heterozygote shows a different phenotype from the homozygous dominant phenotype. Genotype: BB homozygous black Bb heterozygous bb homozygous white Phenotype: BB black fur Bb Grey Fur bb white fur GeneticsCodominant Codominance- traits in which both the alleles are fully expressed in the heterozygote Genotype: BB homozygous black BW heterozygous WW homozygous white Phenotype: BB black fur BW Black and White fur WW white fur GeneticsPolygenic Traits Polygenic- traits in which several genes contribute to the overall phenotype. Examples: skin type of humans has four genes involved and that is why there is such a wide variety of human skin types. GeneticsMultiple Alleles Multiple Alleles-traits that have more than two types of alleles. Example: Blood type There are 3 different alleles for blood type; A,B,O A is dominant to O. B is dominant to O. A and B are Codominant. GeneticsMultiple Alleles Phenotype Genotype O OO A AA or AO B BB or BO AB AB GeneticsSex-linked Sex-linked traits are traits that are located on the sex chromosomes. Majority are located on the X chromosome. Example: colorblindness Remember: Men have a greater chance of having these conditions because they only have one X chromosome. GeneticsStandard Practice When an organism has two different alleles for a trait, is is said to be a. Recessive b. Dominant c. Homozygous d. Heterozygous GeneticsStandard Practice When an organism has two different alleles for a trait, is is said to be a. Recessive b. Dominant c. Homozygous d. Heterozygous GeneticsStandard Practice Use the following chart to answer the questions Blood type is inherited through multiple alleles. A child has type A blood. If the father has type AB blood, what are all thepossible phenotypes of the mother? a. Phenotype O or A b. Phenotype A or AB c. Phenotypes A, B, AB d. Phenotypes O, A, B, AB GeneticsStandard Practice Use the following chart to answer the questions Blood type is inherited through multiple alleles. A child has type A blood. If the father has type AB blood, what are all thepossible phenotypes of the mother? a. Phenotype O or A b. Phenotype A or AB c. Phenotypes A, B, AB d. Phenotypes O, A, B, AB GeneticsStandard Practice Which statement best describes the relationship between an allele and a gene? a. An allele is a variation of a gene that can be expressed as a phenotype. b. An allele is the part of a gene that attaches to messenger RNA molecules. c. An allele is a segment of a DNA molecule that controls replication of a gene. d. An allele is the primary protein made by a gene found in a developing embryo. GeneticsStandard Practice Which statement best describes the relationship between an allele and a gene? a. An allele is a variation of a gene that can be expressed as a phenotype. b. An allele is the part of a gene that attaches to messenger RNA molecules. c. An allele is a segment of a DNA molecule that controls replication of a gene. d. An allele is the primary protein made by a gene found in a developing embryo. GeneticsStandard Practice A trait in cows is determined by two alleles of a single gene: allele R is dominant, and allele r is recessive. What is the probability of the dominant trait being expressed in the offspring of one RR parent and one rr parent? a. 25% b. 50% c. 75% d. 100% GeneticsStandard Practice A trait in cows is determined by two alleles of a single gene: allele R is dominant, and allele r is recessive. What is the probability of the dominant trait being expressed in the offspring of one RR parent and one rr parent? a. 25% b. 50% c. 75% d. 100% All offspring will be heterozygous with Rr genotype so all offspring will express the dominant trait. GeneticsStandard Practice Which form of genetic engineering was used by humans for many years before the discovery of DNA? a. b. c. d. Gene splicing Gene insertion Animal cloning Selective breeding GeneticsStandard Practice Which form of genetic engineering was used by humans for many years before the discovery of DNA? a. b. c. d. Gene splicing Gene insertion Animal cloning Selective breeding Selective breeding results in offspring with desired genetic traits. Farmers and breeders have been doing this for centuries. GeneticsStandard Practice Genetic engineering has led to genetically modified plants that resist insect pests and bacterial and fungal infections. Which outcome would most likely be a reason why some scientists recommend caution in planting genetically modified plants? a. Unplanned ecosystem interactions b. Reduced pesticide and herbicide use c. Improved agricultural and yield profit d. Increased genetic variation and diversity GeneticsStandard Practice Genetic engineering has led to genetically modified plants that resist insect pests and bacterial and fungal infections. Which outcome would most likely be a reason why some scientists recommend caution in planting genetically modified plants? a. Unplanned ecosystem interactions b. Reduced pesticide and herbicide use c. Improved agricultural and yield profit d. Increased genetic variation and diversity Standard Sources of Variation Describe the processed that can alter composition or number of chromosomes (i.e. crossing over, nondisjunction, duplication, translocation, deletion, insertion and inversion Sources of Variation during Meiosis Crossing Over- occurs when two chromosomes physically overlap and exchange chromosome material. This process occurs more often on some chromosomes than other chromosomes and changes the DNA sequence within each chromosomes. This results in an endless number of different possible genetic combinations. Sources of Variation during Meiosis Nondisjunction- (not coming apart) is the failure of chromosome pairs to separate properly during meiosis I or II, during anaphase Chromosomal Mutations Deletion- mutation in which a part of a chromosome or a sequence of DNA is missing Inversion-a mutation that causes a reversal in the order of a segment of a chromosome within the chromosome, or a gene Translocation-transfer of part of a chromosome to a different position on a non-homologous chromosome. Duplication-a mutation in which there are two or more copies of a gene or of a segment of a chromosome. Point Mutations Deletion- a mutation that results when one or two nucleotides are removed Insertion-a mutation that results when one or two nucleotides are added Substitution-a mutation that occurs when when nucleotide is substituted with another nucleotide Note: Deletion and Insertion can result in a frameshift mutation Point Mutations Silent mutations Missense Mutations Does not affect the amino acid Causing a change in the reading of the codons Nonsense Mutations Results in a premature stop command Mutations Mutations Standard Check Which type of change in chromosome composition is illustrated by the diagram? A. Deletion B. Inversion C. Translocation D. Insertion Mutations Standard Check Which type of change in chromosome composition is illustrated by the diagram? A. Deletion B. Inversion C. Translocation D. Insertion Mutations Standard Check What is a source of genetic variation? A. Adaption B. Mutations C. Replication D. Transcription Mutations Standard Check What is a source of genetic variation? A. Adaption B. Mutations C. Replication D. Transcription Standard Describe how the processes of transcription and translation are similar in all organisms. RNA RNA Made of nucleotides Sugar in RNA is ribose and it contains uracil in place of thymine RNA is a single strand of nucleotides RNA-Transcription Transcription is similar to DNA replication, but only one strand of nucleotides is formed. DNA is used as a template to make messenger RNA (mRNA). The mRNA carries the genetic information from DNA to ribosomes in the cytoplasm. RNA-Translation Translation is the process where all three RNA’s (mRNA, rRNA and tRNA) work together to translate the nucleotide language into amino acid language to build proteins. This occurs in the cytoplasm RNA-Standard Check Information on mRNA is used to make a sequence of amino acids into a protein by which of the following processes? A. Replication B. Translation C. Transcription D. Transference RNA-Standard Check Information on mRNA is used to make a sequence of amino acids into a protein by which of the following processes? A. Replication B. Translation C. Transcription D. Transference Standard Describe the levels of ecological organization (i.e., organism, population, community, ecosystem, biome, and biosphere) Ecology Levels of Organization Organism Population Biological community Ecosyststem Biomes Bioshere Ecology Levels of Organization Population Group of organisms of one species that live in the same place at the same time Population density is the number of organisms living in a given area. Ecology Levels of Organization Biological community Group that is made up of several populations interacting with each other If there is a change in one population it can dramatically affect the others living in within the community Ecology Levels of Organization Growth rate Is a change in population size, growth rate can be positive, negative or zero Exponential growth Ecology Levels of Organization Growth rate Is a change in population size, growth rate can be positive, negative or zero Logistic growth Carrying capacity Ecology Levels of Organization When a population reaches its carrying capacity, a number of factors help stabilize it at that size. They are called density-dependent and densityindependent limiting factors. Density-Dependent Limiting Factors Competition Predation Parasitism Crowding/stress Ecology Levels of Organization When a population reaches its carrying capacity, a number of factors help stabilize it at that size. They are called density-dependent and densityindependent limiting factors. Density-Independent Limiting Factors Weather/fires Drought/floods Human activities Ecology Levels of Organization Ecosystem Study the interactions between populations (biotic factors) and their physical surroundings (abiotic factors) Terrestrial ecosystems Aquatic ecosystems Salt water/ marine Fresh water Ecology Levels of Organization Biomes Biosphere Taiga, desert, tropical rainforest Part of Earth that supports life Atmosphere, aquatic and terrestrial Standard Describe how energy flows through an ecosystem (e.g., food chains, food webs, energy) Energy Flow Energy is constantly flowing through ecosystems. Primary source is SUN Terms to Know: Producers/autotrophs Consumers/heterotrophs Decomposers Energy Flow Trophic level Organisms are grouped into trophic levels based on their source of energy----organisms with the same energy sources are on the same trophic level Food chain is a simple diagram that shows how energy and matter flows through an ecosystem Food web is a diagram that shows multiple food chains and the interaction organisms have with each other, in other words a more complex interconnected system of food chains Energy Flow Energy pyramids show how energy decreases at each succeeding trophic level. The total energy transfer from one trophic level to the next is only about 10%. HEY HEY HEY the 10% Rule Energy Flow Standard Check In the food chain below, which population will most likely decrease if snakes are removed from the food chain? Grassgrasshopppergrogsnakehawk a. Grass b. Grasshopper c. Frog d. hawk Energy Flow Standard Check In the food chain below, which population will most likely decrease if snakes are removed from the food chain? Grassgrasshoppperfrogsnakehawk a. Grass b. Grasshopper c. Frog d. hawk Energy Flow Standard Check In the food chain below, identify the initial source of energy for the ecosystem. Grassgrasshoppperfrogsnakehawk a. grass b. sun c. grasshopper d. autotrophs Energy Flow Standard Check In the food chain below, identify the initial source of energy for the ecosystem. Grassgrasshoppperfrogsnakehawk a. grass b. Sun ultimate source for everything c. grasshopper d. autotrophs Energy Flow Standard Check In the food chain below, identify the effect that would occur on one organism if the snake suddenly decreases. Grassgrasshoppperfrogsnakehawk Energy Flow Standard Check In the food chain below, identify the effect that would occur on one organism if the snake suddenly decreases. Grassgrasshoppperfrogsnakehawk Hawks would be harmed because of a decrease in their food supply, could decrease the hawk population due to more competition for available food. Standard Describe how matter recycles through an ecosystem (i.e., water cycle, carbon cycle, oxygen cycle, and nitrogen cycle) Cycles Water Cycle Cycles Water Cycle Evaporates from lakes, streams, oceans Condensation into clouds in the atmosphere Rainfall sends water back to Earth-precipitation Transpiration water given off by plants Cycles Carbon Cycle Cycles Carbon Cycle CO2 in atmosphere is used by plants during photosynthesis and enters the ecosystem CO2 is released back into the atmosphere through respiration, burning, volcanic activity, and artificially through the burning of fossil fuels (coal, oil, gas) CO2 enters aquatic systems through diffusion, used by marine algae, enters ecosystems and then is returned through respiration Cycles Nitrogen Cycles Nitrogen Nitrogen is assimilated into plant tissues due to nitrogen fixing bacteria Nitrogen compounds enter the ecosystem Nitrogen leaves the ecosystem through nitrogenous wastes, death of organisms or denitrifying bacteria which release nitrogen back into the atmosphere Artificial source of nitrogen-fertilizers Cycles Standard Check Which element’s cycle depends on certain kinds of bacteria to keep the element available to other organisms? a. Carbon b. Hydrogen c. Nitrogen d. phosphorus Cycles Standard Check Which element’s cycle depends on certain kinds of bacteria to keep the element available to other organisms? a. Carbon b. Hydrogen c. Nitrogen although bacteria are a part of the other cycles of all the elements listed above, only nitrogen requires the use of nitrogen-fixing bacteria to keep the cycle going d. phosphorus Cycles Standard Check Most of the water on Earth is located in the oceans and has a salinity of about 3.5%. Which statement BEST explains why rain is fresh water and has a very low salinity? A. When water precipitates from oceans, most of the salt remains in the oceans. B. When water evaporates from oceans, most of the salt remains in the oceans. C. When water precipitates from clouds, most of the salt remains in the clouds. D. When water evaporates from clouds, most of the salt remains in the clouds. Cycles Standard Check Most of the water on Earth is located in the oceans and has a salinity of about 3.5%. Which statement BEST explains why rain is fresh water and has a very low salinity? A. When water precipitates from oceans, most of the salt remains in the oceans. B. When water evaporates from oceans, most of the salt remains in the oceans. C. When water precipitates from clouds, most of the salt remains in the clouds. D. When water evaporates from clouds, most of the salt remains in the clouds. Standard Describe biotic interactions in an ecosystem (e.g. competition, predation, symbiosis) Interactions Interspecific Competition Occurs when different species of organisms prey on the same essential resource that is in limited supply Intraspecific Competition Occurs between members of the same species Competition may be harmful to either one or both ends of an interaction Interactions Predation- interaction that is useful for the predator but mostly fatal to the prey Symbiosis-interaction between two species that keep a close physical association, there are three types Parasitism Mutualism Commensalism Interactions Standard Check Which example describes a mutualistic relationship between organisms? A. Young wasps prey on caterpillars Crabs eat the remains of dead fish Ants protect a tree on which they feed Tapeworms feed on food in the intestines of cats Interactions Standard Check Which example describes a mutualistic relationship between organisms? A. Young wasps prey on caterpillars Crabs eat the remains of dead fish Ants protect a tree on which they feed Tapeworms feed on food in the intestines of cats Ecology Standard Check Why are nonnative species often considered a disturbance in an ecosystem? A. They increase mutations B. They compete for resources C. They have special growth needs D. They cause increased biodiversity Ecology Standard Check Why are nonnative species often considered a disturbance in an ecosystem? A. They increase mutations B. They compete for resources C. They have special growth needs D. They cause increased biodiversity Ecology Standard Check Standard Explain how natural selection can impact allele frequencies of a population. Evolution What is natural selection? A mechanism of evolutionary changes that happens when individuals that are better adapted in the challenges of the environment than other individuals survive and reproduce. Evolution Natural selection accounts for the differences among individuals in a population in survival and the ability to successfully reproduce. Essentially, some individuals have alleles that produce phenotypes that help these individuals survive in their environment than other individuals. These successful individuals will then be able to pass these traits to their offspring. Evolution-Darwin Remember: Populations tend to produce more offspring than what the environment can support Resources are limited Individuals need to compete for survival There is variation among the individuals in a given population These variations can be inherited by the offspring Survival of the fittest- the most fit are best adapted to the environment Overtime evolution can occur due to the advantageous traits accumulating in a population Evolution-Darwin Remember: INDIVIDUALS DO NOT EVOLVE POPULATIONS EVOLVE!!!!!! Evolution-Standard Check Ancestors of the koala lived on the ground, but modern koalas live in trees and eat eucalyptus leaves, which are poisonous to most other animals. The difference between the ancestor and modern koalas was caused by A. The presence of homologous structures B. The presence of vestigial organs C. Selective breeding D. Natural selection Evolution-Standard Check Ancestors of the koala lived on the ground, but modern koalas live in trees and eat eucalyptus leaves, which are poisonous to most other animals. The difference between the ancestor and modern koalas was caused by A. The presence of homologous structures B. The presence of vestigial organs C. Selective breeding D. Natural selection Standard Describe the factors that can contribute to the development of new species (e.g., isolating mechanisms, genetic drift, founder effect, migration) Forces of Evolution Genetic Drift Changes in the gene pool of a small population due to CHANCE! Chance events may cause the frequencies of alleles to drift randomly from generation to generation, since the existing gene pool may not be accurately represented in the next generation. Forces of Evolution Genetic Drift The Bottleneck Effect The size of the population may be reduced drastically by such natural disasters as volcanic eruptions, earthquakes, fires, floods, etc. which kill organisms NONSELECTIVELY. By chance some individuals survive. In the small remaining population, some alleles may be overrepresented as some under represent and some alleles may be totally absent. Bottleneck Effect reduces overall genetic variability in a population since some alleles may be entirely absent. Forces of Evolution The Founder Effect The Founder Effect When a few individuals colonize a new habitat, genetic drift is also likely to occur. Genetic drift in a new colony is called the founder effect. The smaller the founding population, the less likely its gene pool will be representative of the original population’s genetic makeup. Forces of Evolution Gene Flow Gene flow is the migration of fertile individuals, or the transfer of gametes between populations. Natural populations may gain of lose alleles by gene flow, since they do not have gene pools which are closed systems. Forces of Evolution Standard Check Horses and tapirs have a common ancestor, but they now look very different from one another. Horses are now grassland animals adapted fro grazing on grass and shrubs. Tapirs are jungle animals that live in dense forests and eat fruit, leaves, and aquatic vegetation. Which of the following led to the development of such differences in the two species? A. Selective breeding B. Convergent evolution C. DNA hybridization D. Natural selection Forces of Evolution Standard Check Horses and tapirs have a common ancestor, but they now look very different from one another. Horses are now grassland animals adapted fro grazing on grass and shrubs. Tapirs are jungle animals that live in dense forests and eat fruit, leaves, and aquatic vegetation. Which of the following led to the development of such differences in the two species? A. Selective breeding B. Convergent evolution C. DNA hybridization D. Natural selection Standards Explain how genetic mutations may result in genotype and phenotypic variations in a population. Mutations Mutations A new mutation that is transmitted in gametes immediately changes the gene pool of a population by substituting one allele for another. Mutations are important to evolution because they are the original sources of genetic variation, which is the raw material for natural selection. Speciation Speciation is When one species splits to form two, that's called speciation. In animals, we say two individuals are different species if they can't interbreed with each other. Sometimes this can happen when two sub-populations are separated. Continents can drift apart, migrating birds can be blown off course, or fruit flies can be bred in different labs. Allopatric speciation is speciation that occurs because populations live in different places. (Contrast this with sympatric speciation, where the two populations might live in the same place but have some other reason why they can't interbreed.) Speciation Speciation Speciation Speciation Speciation Major cause of speciation is isolation. Types of isolation are • • • • Geographical Reproductive Behavioral Temporal Speciation Speciation Types of isolation are • • • • Geographical Reproductive Behavioral Temporal Standard Interpret evidence supporting the theory of evolution (i.e. fossil, anatomical, physiological, embryological, biochemical and universal genetic code) Evidence for Evolution Fossil Record If today’s species came from ancient species, then we should be able to find remains of those species that no longer exist. There are many fossils of organisms that no longer exist, but resemble organisms that do exist today. Fossil record creates a geological time scale. Evidence for Evolution Comparative Anatomy Homologous structures-common ancestor, structures that are similar in structure but different in function Example: human arm and bat wing Evidence for Evolution Comparative Anatomy Vestigial Organs Seemingly functionless parts, snakes have tiny pelvic and limb bones, humans have tail bones Evidence for Evolution Comparative Biochemistry and DNA There is biochemical similarity in all living things. Organisms that are closely related will have less differences in their proteins, which means that the amino acid sequence will be similar which means the DNA nucleotide sequence will be similar. Evidence for Evolution Comparative Embryology Developing organisms have similarities in their early stages of development. Evidence for Evolution Observation of Species change WolvesDogs Light colored peppered mothdark colored peppered moth Evidence for Evolution Standard Check Fossils of Archaeopteryx show that this animal had feathers, like a bird. It also had a bony tail, teeth, and claws on its wings, like a reptile. These fossils are evidence that support the idea that A. Birds and reptiles have a common ancestor B. Birds have changed very little over millions of years C. Reptiles species are more advanced than bird species D. Reptiles are warm-blooded like birds Evidence for Evolution Standard Check Fossils of Archaeopteryx show that this animal had feathers, like a bird. It also had a bony tail, teeth, and claws on its wings, like a reptile. These fossils are evidence that support the idea that A. Birds and reptiles have a common ancestor B. Birds have changed very little over millions of years C. Reptiles species are more advanced than bird species D. Reptiles are warm-blooded like birds Evidence for Evolution Standard Check Which of the following is considered by most biologists to be the most accurate in supporting the theory of evolution? A. Fossils B. Embryology C. DNA sequencing D. Genetic equilibrium Evidence for Evolution Standard Check Which of the following is considered by most biologists to be the most accurate in supporting the theory of evolution? A. Fossils B. Embryology C. DNA sequencing D. Genetic equilibrium DNA sequencing is the most accurate tool for determining relatedness. Evidence for Evolution Standard Check Which of the following is considered by most biologists to be the most accurate in supporting the theory of evolution? A. Fossils B. Embryology C. DNA sequencing D. Genetic equilibrium DNA sequencing is the most accurate tool for determining relatedness. STUDENTS I think you rock…..and I want you all to know that you are so much higher than 1500’s so show the state how great you ALL really are. BEST OF LUCK TOMORROW I WILL BE THINKING OF YOU ALL!!!!!!!!!!